When, for example, a building is constructed, the framework of the building must be made. FIG. 1 shows an example of a connection between two steel beams 2, 1. The connection comprises an endplate 4, which is fixed (normally welded) to the smaller beam 1, and bolted joints 3 that finally fix the smaller beam to the flange 5 of the bigger beam 2.
FIG. 2 shows an example of a connection among three beams 21, 22, 23. The first site beam 21 is connected to the flange 23A of the main beam 23 using an endplate 24 and bolted joints 25. The second side beam 22 is connected to the other side of the main beam using the same bolted joints 25, but now the endplate of the second beam is different due to the different size of the beam. This type of connection is called a two-sided connection. As can be noticed, there may exist a huge number of different connections between at least two construction elements. Naturally, a connection may be between a column and a beam, or between two columns etc.
At present, dedicated software (and/or hardware) is used for forming connections between construction elements. It is possible to define connection parameters, such as number of bolts, bolt locations, and plate dimensions. A single connection may comprise several dozens of attributes, which affect connection parameters and a final connection. The known solutions use fixed connections from among a desired connection (or connections) is searched. Further, the dedicated software or the hardware often has an option to save connections already made for future use. The saved connections can be used in the same kind of new situations (same elements, conditions, etc.) This feature can be called as an auto-default function.
The auto-default function utilizes a logic structure for using different connections already made. The logic structure makes it possible to search connections and to form new connections, whose locations in turn are determined in the logic structure. Furthermore, the auto-default function may automatically search a new connection in a modification situation. For example, the auto-default function searches a new connection when one of the beams to be connected changes.
FIG. 3 shows an example of the auto-default function in a flow chart. Let a task be to form a construction of an endplate of the connection. If the desired endplate already exists, it can be used, and the desired endplate is preferably searched from the group of existing endplates. The search is often divided into several levels. On level 1, elementary cases of the endplate are defined, on level 2 more special cases, and level 3 yet more special cases. It should be noticed that a number of the levels can be any suitable number depending on the complexity of endplate structures. On level 1 in FIG. 3, the logic structure of the auto-default function determinates 31 whether the desired endplate belongs to level 1 or level 2. The determination depends on, for example, the features of the steel beam, for which the endplate is formed. If the type of the desired endplate is a kind of modification that it does not comprise more specified features already determined, the auto-default function uses a basic endplate structure MOD1, which already exists. If the desired endplate comprises specified features, which already exist on level 2, the search continues on level 2.
On level 2, the logic structure has been constructed so that the suitability of a certain endplate modification is checked first. If this modification does not match with the desired endplate, the next endplate modification is checked and so on until a suitable endplate is found, the search continues on the next level, or the basic modification is selected. In FIG. 3, the endplate modification MOD21 is checked 32 first. If MOD21 is suitable, it is selected to be the endplate. Otherwise, the endplate modification MOD22 is checked 33. If MOD22 is suitable, it is selected to be the endplate. Otherwise, the endplate modification MOD23 is checked 34. If MOD23 is suitable, it is selected to be the endplate. Otherwise, the endplate modification MOD24 is checked 35. If MOD24 is suitable, it is selected to be the endplate. Otherwise, it is checked 36 does the desired endplate belongs to level 3. If the endplate belongs to the level 3, which comprises yet more specified features of the endplate, the search continues on level 3. Otherwise the basic endplate structure MOD1 is selected to be the desired endplate. It should be noticed that instead of using MOD1 as a basic default structure, level 2 could have (as all levels may have) its own basic default endplate structure 39.
On level 3, the search proceeds similarly as on level 2. The endplate modification MOD31 is checked 37 first. If MOD31 is suitable, it is selected to be the endplate. Otherwise, the endplate modification MOD32 is checked 38. If MOD32 is suitable, it is selected to be the endplate. Otherwise the basic endplate structure MOD1 is selected to the desired endplate. Alternatively, a level 3 specific default endplate may be selected.
So, if the MOD31 is the desired endplate, the search goes through the logic structure elements 31, 32, 33, 34, 35, 36, and 37. However, a problem occurs when MOD31 is the closest endplate desired to construct, but not exactly the one. Thus, MOD31 must be modified to form a new endplate (for example fewer bolts) by a user. The new endplate may be saved into the group of already saved endplates. As can be noticed, a number of saved endplates (or other connection elements) may increase very huge and the saved cases may be in any part of the logic structure. It is clear that this kind of system is tedious to set up and update, and difficult to maintain.
Especially the logic structure used, comprising several levels and logic structure components, makes the set up and the maintenance tedious. It is also known to use a matrix as a logic structure, but it is even more tedious and difficult than the tree structure of FIG. 3.
In real applications, the parameters of elements (structures) come from different sources. An engineer may give, for example, a number of bolts or plate dimensions. General design definitions may define, for example, a weld size based on the forces of on an element. Manufactures have their own preferences, such as type of bolts. Thus, the auto-default function works properly, when the fixed elements comprise exactly the same constructions. But when a project comprises elements from different manufactures, structures are different, connections are different, and so on. Thus the existing auto-default set up is relatively useless, so it must be set up again for the new project as well.
So, the known solutions contain a great number of predefined solutions, making them relatively fixed and rigid to use. The maintenance and updating of the known systems are very tedious or even impossible because of the complexity of the systems. For example, if the setup of the system has been made for the practice of a certain country, it may or may not be used according to the practice of another country. Or only a part of the existing system is usable, and even then the complexity of the system may prevent the use.
Due to these mentioned matters, it is clear that the present solutions need improvements. The goal of this invention to alleviate the above mentioned drawbacks of known solutions. The goal is achieved in a way described in the claims.